diff --git a/src/render/opengl/SDL_render_gl.c b/src/render/opengl/SDL_render_gl.c
index 77248e421..279652f12 100644
--- a/src/render/opengl/SDL_render_gl.c
+++ b/src/render/opengl/SDL_render_gl.c
@@ -1233,7 +1233,6 @@ GL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                     Uint32 pixel_format, void * pixels, int pitch)
 {
     GL_RenderData *data = (GL_RenderData *) renderer->driverdata;
-    SDL_Window *window = renderer->window;
     Uint32 temp_format = SDL_PIXELFORMAT_ARGB8888;
     void *temp_pixels;
     int temp_pitch;
@@ -1253,7 +1252,7 @@ GL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
 
     convert_format(data, temp_format, &internalFormat, &format, &type);
 
-    SDL_GetWindowSize(window, &w, &h);
+    SDL_GetRendererOutputSize(renderer, &w, &h);
 
     data->glPixelStorei(GL_PACK_ALIGNMENT, 1);
     data->glPixelStorei(GL_PACK_ROW_LENGTH,
diff --git a/src/render/opengles/SDL_render_gles.c b/src/render/opengles/SDL_render_gles.c
index 920b35fb0..0ec21da07 100644
--- a/src/render/opengles/SDL_render_gles.c
+++ b/src/render/opengles/SDL_render_gles.c
@@ -1006,7 +1006,6 @@ GLES_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                     Uint32 pixel_format, void * pixels, int pitch)
 {
     GLES_RenderData *data = (GLES_RenderData *) renderer->driverdata;
-    SDL_Window *window = renderer->window;
     Uint32 temp_format = SDL_PIXELFORMAT_ABGR8888;
     void *temp_pixels;
     int temp_pitch;
@@ -1022,7 +1021,7 @@ GLES_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
         return SDL_OutOfMemory();
     }
 
-    SDL_GetWindowSize(window, &w, &h);
+    SDL_GetRendererOutputSize(renderer, &w, &h);
 
     data->glPixelStorei(GL_PACK_ALIGNMENT, 1);
 
diff --git a/src/render/opengles2/SDL_render_gles2.c b/src/render/opengles2/SDL_render_gles2.c
index f52afc15a..fafc9da59 100644
--- a/src/render/opengles2/SDL_render_gles2.c
+++ b/src/render/opengles2/SDL_render_gles2.c
@@ -1508,7 +1508,6 @@ GLES2_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                     Uint32 pixel_format, void * pixels, int pitch)
 {
     GLES2_DriverContext *rdata = (GLES2_DriverContext *)renderer->driverdata;
-    SDL_Window *window = renderer->window;
     Uint32 temp_format = SDL_PIXELFORMAT_ABGR8888;
     void *temp_pixels;
     int temp_pitch;
@@ -1524,7 +1523,7 @@ GLES2_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
         return SDL_OutOfMemory();
     }
 
-    SDL_GetWindowSize(window, &w, &h);
+    SDL_GetRendererOutputSize(renderer, &w, &h);
 
     rdata->glPixelStorei(GL_PACK_ALIGNMENT, 1);